Drive Motor Power Inverter Module Description and Operation: Overview

The power inverter module, often referred to as the drive motor generator power inverter module, converts high voltage direct current (DC) electrical energy to 3 phase alternating current (AC) electrical energy. The power inverter module contains 2 motor control modules and the hybrid/EV powertrain control module 1. One of the motor control modules operates the drive motor based upon power inverter module commands. The second motor control module controls the auxiliary transmission fluid pump. The hybrid/EV powertrain control module 1 and the motor control modules share the power inverter module ignition voltage circuit, battery voltage circuits and chassis ground. All three modules are flash-programmable micro-processors. The power inverter module is cooled with pre-mixed Dexcool® circulating through a cooling system that is separate from the engine cooling system. The hybrid cooling system utilizes a heat exchanger at the front of the vehicle and electric pumps to circulate the coolant. The ECM monitors a temperature sensor in the hybrid cooling system and operates the radiator fan and the hybrid coolant pumps in response to system temperature.